This invention relates generally to an improved hinge pin assembly for use in connecting linkage components. More particularly, but not by way of limitation, this invention relates to an improved hinge pin assembly that is self lubricating, that is sealed, and that maintains the sealing relationship despite distortions occurring in the clevis brackets.
One type of pin that is commonly used in the industry for pivotally connecting linkage components in a front end loader is referred to as a cartridge pin. That is, the pin is composed of a relatively large number of elements which are preassembled and then placed into the aligned holes in the mounting brackets and the bore in the arm to pivotally connect such apparatus. An example of the cartridge type pin assembly is illustrated in U.S. Pat. No. 4,096,957 issued on June 27, 1978 to Lowell P. Iverson et al. Pins of that type have functioned generally satisfactorily, but they consist of a welded unit that includes the bearings or bushings, as well as the seals that isolate the lubricant between the bushing and the main body of the pin. Accordingly, when it is necessary to replace the pin cartridge, it is necessary to replace the entire unit. Further, some difficulty has been encountered due to the distortion that occurs when uneven loads are encountered by the bucket causing the clevis brackets to move slightly relative to each other, bringing the faces thereon into engagement with the sides of the loader arm. When this occurs, substantial wear occurs on the rubbing components.
Another patent illustrating a hinge pin assembly is U.S. Pat. No. 4,398,862 issued Aug. 16, 1983 to William L. Schroeder. That pin assembly includes an internally lubricated pin with a refillable lubricant chamber therein and appropriate seals for preventing the escape of lubricant from the assembly. However, because of the tapered surfaces and annular wedges involved, the pin of this patent is relatively expensive to manufacture, somewhat difficult to replace, and the seals therein are subject to a change in the axial dimension of the hinge joint which may cause either unusual seal wear or leakage when the joint is subject to extreme use.
An object of this invention is to provide an improved hinge pin assembly that is relatively inexpensive to manufacture, is constructed to maintain the seal integrity, self lubricating, and avoids wear between the loader linkage eye and the clevis brackets when uneven loads are encountered.